Local and Global Public Health and Emissions from Concentrated Animal Feeding Operations in the USA: A Scoping Review

Abstract

Up to 1.6 million tons of waste is produced annually by each of more than 21,000 concentrated animal feeding operations (CAFOs) located in the United States (USA). These operations give rise to externalities, including adverse local and global health impacts from CAFO waste emissions, which can potentially outweigh their economic viability. However, a shortage of evidence synthesis research exclusively on the impacts of USA-based CAFO waste emissions may hinder effective policy development. This scoping review (ScR) study, adhering to the guidelines from the Joanna Briggs Institute, conducted a search in databases including Scopus, Web of Science, PubMed, and Embase in May 2020, resulting in ten publications that met the inclusion criteria. The results suggest possible exposure of CAFO workers to multidrug-resistant Staphylococcus aureus (MDRSA), campylobacteriosis, and cryptosporidiosis. Communities near CAFOs experienced higher rates of adverse health impacts compared to those in non-CAFO areas, with patterns suggesting that proximity may correlate with increased odds of detrimental health effects. Implicit global health threats include methicillin-resistant Staphylococcus aureus (MRSA), MDRSA, campylobacteriosis, tuberculosis, and cryptosporidiosis. These studies provide foundational insights into CAFO proximity, density patterns, and adverse public health effects, indicating a need for evidence-informed environmental health policies to minimize local and global risks.

Keywords: air pollution; global health; health impacts; industrial livestock production; occupational health.

Figure 1

Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews (PRISMA-ScR) flow diagram [73]. Ten studies met the inclusion criteria of the ScR.

Figure 2

Number of studies by livestock type (n = 3), state (n = 5), and other (laboratory) (n = 2).

Figure 3

Conditions, exposures, or symptoms investigated in occupational health studies. Miscellaneous symptoms included in Figure 4. Data from Su et al. [74], Davis et al. [75], Knoell et al. [76], Ramos et al. [77], and Wyatt et al. [78]. * Multidrug-resistant Staphylococcus aureus.

Figure 4

Self-reported condition and symptom data from CAFO workers in Missouri. Data source: Ramos et al. [77].

Figure 5

Number of S. aureus-resistant isolates in ambient air at swine facility in NC. Data source: Davis et al. [75].

Figure 6

Conditions, symptoms, and exposures investigated in community health studies. Data from Beresin et al. [79], Kravchenko et al. [80,81], Schulz et al. [82], and Loftus et al. [83]. * Methicillin-resistant Staphylococcus aureus.